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W Kenn

Publications and source records attributed to W Kenn.

At least 19 recordsLinked to original sources
PubMed2005

Accessory joints between basiocciput and atlas/axis in the median plane.

To explore the many osseous irregularities that are found in the area between the basiocciput, the anterior arch of the atlas and the tip of the dens axis we studied 99 cadaver specimens using magnetic resonance tomography (MRT), computed tomography (CT), median saw-cut sections, and histological sections. Additionally, "dry" specimens of the skull (n = 110), atlas (n = 56), and axis (n = 33) were investigated. In the median plane, the dry and cadaver specimens exhibited osteoarthritis-related osseous outgrowths and osteophytes of the articular surfaces of the median atlanto-axial joint (n = 63), and the presence of congenitally developed free ossicles (n = 22) and of third occipital condyles (n = 3). The largest osteophytes (giant osteophytes) (n = 4) of the anterior arch of the atlas formed osseous contact zones with the basiocciput that were visible histologically as real joints and were designated accessory median atlanto-occipital joints. The third occipital condyles also formed osseous contact zones, visible histologically as real joints, with the anterior arch of the atlas or with the tip of the dens, and were designated accessory atlanto-occipital or occipito-odontoid joints. Frequent free ossicles, incorporated into the accessory joint, were found by histological examination to be covered with hyaline cartilage.

Adult↗
PubMed2005

[Deep neck infections and mediastinitis].

Deep neck infections and subsequent mediastinitis can occur as lethal complications after endotracheal intubation. A 53 year old female patient developed a neck abscess and mediastinitis due to esophageal perforation after endotracheal intubation. Neck and mediastinal exploration were performed as primary surgical treatment in cooperation with thoracic surgeons. Drainage tubes for neck and mediastinum were inserted and irrigated frequently. The abscess cavity was re-examined twice after primary surgery. Microbiological tests were performed at regular intervals to guarantee appropriate antibiotic therapy. This case demonstrates the importance of early and extensive surgical intervention and the necessity of interdisciplinary cooperation in treating such infections.

Abscess↗
PubMed2005

[Individualized dose requirement for spiral-CT analysis of the abdomen].

PURPOSE: To search for individualized scan protocols that provide adequate diagnostic information with minimal radiation exposure for abdominal CT in adults. MATERIAL AND METHODS: Beginning with standard settings (120 kVp, 200 mA, 0.75 s, CTDI (w = 11.7 mGy)), which are in the lowest quartile of the actual German radiation dose survey, 119 adults were examined using a single-row detector helical CT with 8 mm collimation and a pitch of 1.5. The individualized scan protocol was defined by repeating the reference scan up to 3 times with different radiation doses following a predefined iteration scheme. The image qualities with standard dose and with individualized dose were assessed independently by 3 radiologists blinded to the exposure parameters. The individualized dose was correlated with the diameter of the patients. RESULTS: The patient diameters varied from 16 to 35 cm and correlated with individualized radiation doses CTDI (w) from 6.4 to 17.6 mGy. We found an exponential correlation (y = 52.3 x e (0.05 x); r(2) = 0.48; p < 0.001) between required tube current (mA) and a. p. diameter (cm) in the epigastric region in adults. CONCLUSION: Maintaining constant exposure parameters results in unnecessary radiation exposure in patients with a diameter of less than 27 cm measured in anterior-posterior direction in the epigastric area. The radiation exposure in adult abdominal CT can be reduced up to 45 % by individualized selection of the tube current without adversely affecting diagnostic performance.

Adult↗
PubMed2004

Adrenal tumors: how to establish malignancy ?

Discerning malignancy in adrenal tumors largely influences disease management and is, therefore, of utmost importance to both patient and physician. Clinical presentation (e.g. virilization) and baseline hormonal evaluation (e.g. high serum DHEAS) are occasionally of great value but usually provide only limited help in predicting malignancy. The probability of malignancy is clearly related to tumor size, as almost all lesions <3 cm are benign whereas a diameter of >6 cm indicates a high risk of malignancy. Computed tomography (CT) and magnetic resonance imaging (MRI) both contribute significantly to the characterization of adrenal masses. If the attenuation of a homogeneous mass with smooth border is 10 Hounsfield units or less in unenhanced CT the diagnosis of a lipid rich adenoma is established. Similarly, enhancement washout of more than 50% in CT at 10-15 min suggests a benign lesion. In MRI both rapid contrast enhancement after gadolinium followed by rapid washout and signal intensity loss using opposed-phase image in chemical shift analysis also indicate the presence of an adenoma. In contrast, adrenal carcinomas--but also pheochromocytomas--typically present as inhomogeneous lesion with intermediate-to-high intensity on T2 images in MRI. Margins and enhancement after contrast media in CT are irregular in adrenal carcinoma. Other imaging techniques either offer little additional information (NP-59 scintigraphy) or have not yet been fully established (positron emission tomography). Fine needle aspiration/cut biopsy is at present restricted to patients with a known extra-adrenal malignancy and suspected adrenal metastasis as the only evidence of disseminated disease. Adrenal tumors classified as benign undergo follow-up imaging to assess tumor growth. If an increase in diameter of >1 cm is seen, surgical removal is recommended. Even after tumor removal the diagnosis of dignity may remain difficult. Diagnostic scores together with new immunohistological markers are the methods of choice to assess malignancy. In conclusion, an interdisciplinary approach with a structured use of available diagnostic tools is needed to classify adrenal tumors correctly.

Adrenal Gland Neoplasms↗
PubMed2004

[Perineal hernia: an undescribed complication following operative repair of vault vaginal prolaps].

The presented case reports the treatment of a 80-year-old V gravida IV para suffering from a large perineal hernia and rectocele after vaginal hysterectomy and subsequently performed threefold colpocleisis due to recurrent vault vaginal prolaps.[nl]Since perioperative morbidity and mortality of geriatric patients differ not significantly from thoses of younger women age should not be used as an argument to withhold elderly organ preserving operative strategies with low recurrence rates.

Aged↗
PubMed2003

Transient bone marrow edema syndrome progressing to avascular necrosis of the hip - a case report and review of the literature.

Transient bone marrow edema syndrome (TMES) is a rare disease of unknown etiology. Diagnosis is made by exclusion. There is still controversy as to whether TMES is considered to be a reversible form of avascular necrosis (AVN), a disease entity of its own or a form of non-traumatic algodystrophy. We here describe the extremely rare occurrence of three cases of TMES that progressed to AVN.

Adult↗
PubMed2003

Transient marrow edema syndrome of the hip: results after core decompression. A prospective MRI-controlled study in 22 patients.

BACKGROUND: Transient marrow edema syndrome (TMES) of the hip is a disease of acute onset and severe functional disability. There is histological evidence for an ischemic etiology of TMES of the hip. Core decompression as applied for avascular necrosis (AVN) of the hip is therefore a therapeutic alternative to conservative therapy, the latter leading only to a reduction of symptoms but never a shortening of the course of the disease. METHODS: Between January 1998 and June 2000, 22 hips with TMES were treated with core decompression in our department. TMES was diagnosed by exclusion. MRI was done preoperatively and at 6 months postoperatively. The postoperative MRI result was classified into three categories. RESULTS: After an average of 7.2 (range 1-30) days, all patients were pain-free after core decompression. In 2 patients, TMES progressed to AVN despite core decompression. All others had no signal alterations of the head of the femur on MRI after 6 months. The postoperative Harris Hip Score (HHS) in patients with TMES was on average 93.7 (range 77-95); in patients with AVN, the postoperative HHS was 47 (range 45-49). CONCLUSION: Our results demonstrate that core decompression of the hip significantly shortens the natural course of disease of TMES of the hip.

Adult↗
PubMed2003

Ultrasonographic appearance of os acromiale.

AIM: Ossa acromiale are rare anatomical conditions and have been evaluated with plain radiographs, CT- and MRI-scans, but not with ultrasound. The purpose of this study was to evaluate the appearance and the characteristics of os acromiale with ultrasound. METHODS: 25 patients with unilateral radiologically prediagnosed os acromiale had bilateral examination with ultrasound. Recorded details were bilateral appearance, the width of the non-ossified space and the shape of the bony margins of the os acromiale. As a control group 25 patients without radiological appearance of os acromiale had identical ultrasound examination. RESULTS: The os acromiale could be identified in all 25 patients (100%) with radiologically confirmed os acromiale. In 12 patients an os acromiale could be identified on the contralateral side (48%). The average width of the non ossified space was 4.3 mm (2.5 to 7.6 mm). Three different sonographic types of bony margins of the os acromiale and the acromion exist: Type I with flat bony margins; Type II with marginal osteophytes and Type III with inverted bony margins. In the control group no os acromiale could be identified. CONCLUSION: With ultrasonographic assessment, os acromiale can be accurately identified in each case. Three differently shaped bony margins exist. Ultrasound can give additional information about the os acromiale if radiological assessment is unclear because of superimposing bones.

Acromion↗
PubMed2003

[Direct MR arthrography of the wrist- value in detecting complete and partial defects of intrinsic ligaments and the TFCC in comparison with arthroscopy].

PURPOSE: To assess the value of two-compartment magnetic resonance (MR) wrist arthrography in comparison with diagnostic arthroscopy for the evaluation of defects of the triangular fibrocartilage complex (TFCC) and intrinsic ligaments in patients with refractory wrist pain. The direct MR arthrographies were evaluated following arthroscopic classification with consideration of complete and partial defects. The distinction between these types of lesions has clinical implications for treatment procedures such as cast immobilization, arthroscopic debridement, surgical repair or partial intercarpal arthrodesis. MATERIALS AND METHODS: Seventy-five patients (25 female, 50 males, mean age 38.3 years) who suffered from refractory wrist pain without radiography evidence of carpal instability underwent two-compartment wrist MR arthrography. Under aseptic conditions a solution of gadopentate dimeglumine and iodinated contrast agent (concentration 2.5 mmol/l) was injected into the radiocarpal and midcarpal joints under fluoroscopy guidance. Using a scanner of 1.5 T field strength and a wrist-coil following sequences were acquired: coronary and sagittal T (1)-weighted spin-echo (SE) sequences (TR 500 ms, TE 25 ms, matrix 512 x 512.3 mm) and coronary fast low angle shot (FLASH) 3D sequences (TR 24 ms, TE 11 ms, matrix 256 x 256, 1.5 mm, flip angle 50 degrees). All patients underwent subsequent arthroscopy of the wrist. The direct MR arthrographies were evaluated retrospectively by two observers experienced in the diagnosis of wrist pathology. They were not aware of the clinicial, arthrographic and arthroscopic findings. Pathology of the scapholunate ligament was classified according to the guidelines of the German Society of Hand Surgery (DGH), lesions of the lunotriquetral ligament according to Hempfling and lesions of the TFCC according to Palmer. RESULTS: Twenty-five complete and 47 partial defects were detected arthroscopically (TFCC: 21/20, scapholunate ligament: 3/18, lunotriquetral ligament: 1/9). The TFCC showed a higher prevalence for degenerative lesions (11 type 2C-lesions and 20 type 2A/B lesions) than for traumatic lesions (5 type 1A lesions, 5 type 1D lesions). For direct MR arthrography, the obtained sensitivities and specificities in assessing complete defects were 96 % and 99.6 % (T (1)-weighted SE) and 92 % and 100 % (FLASH 3D), respectively. For all partial defects, sensitivities and specificities were 68.1 % and 93.3 % (T (1)-weighted SE) and 63 % and 96.1 % (FLASH 3D), respectively. For depicting partial defects of the scapholunate ligament the T (1)-weighted SE sequence (83.3/95.5 %) was superior to the FLASH 3D sequence (64.7/96.6 %), p < 0.05. For the evaluation of the TFCC (T (1)-weighted SE: 65/94.4 %, FLASH 3D: 70/94.6 %) and the lunotriquetral ligament (T (1)-weighted SE: 44/89.4 %, FLASH 3D: 44 /96.7 %), direct MR arthrography showed an insufficient correlation with arthroscopy. CONCLUSION: Direct MR arthrography proved to be of equal value compared with diagnostic arthroscopy in detecting complete defects of the intrinsic ligaments and the TFCC. The method has the potential of replacing diagnostic arthroscopy for the evaluation of the intrinsic ligaments and the TFCC. The T (1)-weighted SE sequence appeared to be superior to the FLASH 3D sequence in evaluating partial defects of the scapholunate ligament. Direct MR arthrography did not reliably detect partial defects of the TFCC and the lunotriquetral ligament.

Adult↗
PubMed2002

Current concepts in imaging of laryngeal and hypopharyngeal cancer.

In adjunct to direct laryngoscopy, CT and/or MRI are needed for an accurate staging of laryngeal and hypopharyngeal carcinomas because both cross-sectional imaging modalities are known to reliably evaluate deep tumor infiltration. Except for the clinical background, this article reviews technical aspects of CT and MRI, the pathologic appearance of laryngeal and hypopharyngeal carcinomas, and therapeutically relevant diagnostic aspects.

Adult↗
PubMed2002

[Primary glomangioma of the liver. A new differential benign liver tumor diagnosis].

Glomus organs are arteriovenous anastomoses which control the thermoregulation of the extremities. Benign tumors of these glomus organs, termed "glomangiomas", are therefore most frequently located in the fingers and toes. Case reports of primary glomangiomas in the respiratory- and gastrointestinal tracts as well as in the genital organs have been published. On the other hand, glomus tumors of the liver have not yet been described. We report the case of a 61-year-old patient with a smooth subcapsular lesion within the liver detected by a routine ultrasound scan. Further diagnostic imaging did not match with one of the common liver tumors. The diagnosis of a glomangioma was finally made by liver biopsy and subsequent histology. A review of the literature revealed a potential transformation of glomangiomas. Since the patient reported on inappetence weight loss and the tumor showed growth tendency, the indication for surgical excision was made. Final histologic investigation revealed no signs of malignancy. The primary glomangioma of the liver is a new differential diagnosis of benign liver tumors. As there is a possibility of malignant degeneration, we propose the decision for surgical removal once there are clinical symptoms and a growth tendency of the lesion.

Diagnosis, Differential↗
PubMed2002

High resolution contrast enhanced MR-angiography of the hand arteries: preliminary experiences.

BACKGROUND: In contrast to magnetic-resonance-angiography (MRA) of the peripheral vessels of the lower extremity, which gains more and more clinical application, MRA of the hand arteries is still exceptional. Our objective was to introduce an appropriate protocol for high resolution contrast-enhanced MR-angiography of the hand arteries. PATIENTS AND METHODS: 7 healthy volunteers and 13 patients with suspected hand artery obstructions underwent MRA. The examinations were performed on a 1.5 T system equipped with a flexible surface coil. A modified 3D-gradient-echo sequence was used. Criteria for image analysis were the overall image quality, vessel visibility and the timing of the contrast material bolus. RESULTS: In the volunteer group delineation of the superficial or deep palmar arch, common palmar digital arteries and of the proximal and middle segments of the digital arteries was possible. No pathologic findings were seen in the volunteer group. In 10 patients MRA revealed pathologic findings. In 9 examinations bolus-timing was correct, 7 examinations showed incomplete arterial enhancement, 4 examinations showed venous overlay. CONCLUSIONS: Contrast enhanced MR-angiography of the hand arteries in the described technique is a promising method. Compared to intraarterial digital subtraction angiography (IA-DSA) MRA still has limitations concerning spatial and temporal resolution. For clinical evaluation comparative studies with IA-DSA are necessary.

Adult↗
PubMed2002

[2D-SPLASH spectroscopy to determine the fat/water ratio in the muscle of the rotator cuff].

AIM: The degree of fatty infiltration of the rotator cuff is an important factor for the prognosis of an operative reconstruction afterrotator cuff tear. The aim of this work was to develop a method using a clinical MR scanner that allows the quantification of the fat/water ratio with the necessary spatial resolution. METHOD: A SPLASH sequence consisting of 19 complex 2D-FLASH images was implemented on a clinical 1.5 T MR scanner. The echo time was gradually increased from 5.0 ms to 50.0 ms. A spatial in plane resolution of 1.17 mm, a spectral resolution of 0.33 ppm and a spectral width of 6.25 ppm were achieved in a total acquisition time of about 3 min. The quantitative evaluation of the spectra in arbitrarily shaped regions of interest (ROIs) was obtained using a home-built reconstruction program and the time domain fit program AMARES. RESULTS: Phantom studies show a linear relation of the concentration determined by SPLASH spectroscopy (r = 0.997). Because of the high spatial resolution and the possibility to evaluate arbitrarily shaped ROIs, the determination of the fat/water ratio in single muscles in the shoulder has been possible. CONCLUSIONS: By the use of the 2D-SPLASH sequence the degree of fatty infiltration in the rotator cuff can now be determined quantitatively for the first time.

Adipose Tissue↗
PubMed2002

[Time-resolved MR angiography of the renal artery: morphology and perfusion].

PURPOSE: To prove the hypothesis that renal artery stenosis and changes in renal perfusion can be detected with contrast-enhanced time-resolved MR angiography in a single examination. MATERIAL AND METHODS: In 71 patients, 137 renal arteries and 14 accessory renal arteries were studied. The examinations were performed on a 1.5 T system. A T 1 -weighted gradient echo sequence with a temporal resolution of 7 s was used. Single dose of contrast material (0.1 mmol/kg Gd-DTPA) was injected with a power injector with a flow rate of 2 ml/s. Criterion for the assessment of renal perfusion was the slope ratio of the signal intensity time curve in both kidneys. RESULTS: Forty renal artery stenoses and one occlusion of a renal artery were detected. In 48 kidneys (35 %) segmental arteries were evaluated. The accuracy of the slope ratio (limit value 0.75) concerning the detection of unilateral renal artery stenosis was 92.6 % (sensitivity 75 %, specificity 95.7 %). CONCLUSION: Time-resolved MR angiography can detect changes in renal perfusion in patients with unilateral renal artery stenosis.

Adolescent↗
PubMed2002

[Interindividual-variability of the analysis of regional myocardial wall function after myocardial infarction and revascularization].

PURPOSE: The gold standard for diagnosis myocardial viability is the functional recovery after revascularization. Aim of the study was to compare (1) qualitative analysis and (2) quantitative wall thickening by cine MRI and (3) circumferential shortening by tagged MRI the analysis of regional wall function of an infarcted area before and after revascularization. MATERIAL AND METHODS: Ten patients (age 60 +/- 11 years) with infarct-associated regional left ventricular wall motion abnormalities were examined by cine and tagged MRI on average two weeks after the myocardial infarction and re-examined three months after revascularization. Eight healthy volunteers served as a control for tagged MRI. Interobserver-variabilities of two observers were calculated using the kappa-statistics for grading of wall motion abnormalities as well as for detection of functional recovery by qualitative analysis, measurement of wall thickening of cine MRI, and measurement of circumferential shortening by tagged MRI, respectively. RESULTS: Grading of wall motion abnormalities revealed interobserver-variabilities of the study and control group of kappa = 0.8 and kappa = 0.84, kappa = 0.02 and kappa = 0.5, and kappa = 0.1 and kappa = 0.17 for qualitative analysis, wall thickening analysis and measurement of circumferential shortening, respectively. The interobserver-variability for the definition of wall motion recovery was kappa = 0.8 for all three methods. CONCLUSION: Qualitative analysis of wall motion abnormalities has the lowest interobserver-variability for the grading of wall motion abnormalities. The interobserver-variabilities of qualitative and quantitative analysis are comparable for the diagnosis of regional wall motion recovery. Thus, qualitative analysis of cine MRI can be used for grading regional wall motion in clinical studies.

Aged↗
PubMed2002

Presentation of an unusual benign liver tumor: primary hepatic glomangioma.

Glomus organs are small arteriovenous anastomoses chiefly responsible for thermoregulation of the distal portion of the extremities. Glomangiomas are benign tumors of these bodies. They occur preferentially in the fingers and toes, but some case reports describe primary glomangiomas in the respiratory or gastrointestinal tract and genitals. To date, no glomangiomas of the liver have been reported. We report on a 61-year-old patient in whom routine ultrasound disclosed a subcapsular well-defined mass in the liver. Further imaging showed that the mass did not correspond to any of the usual liver tumors. Biopsy finally revealed it to be a primary glomangioma of the liver. Clinically, there was lack of appetite and weight loss over a period of several months. Owing to the possibility of malignant transformation of glomangiomas, as described in the literature, the tumor was excised under existing clinical symptoms and continued slow growth. Further histological evaluation of the tumor did not reveal malignancy. Primary glomangioma of the liver is a new differential diagnosis for benign liver neoplasms. Because there is a potential for malignant transformation, the existence of clinical symptoms and continuing growth are indications for resection.

Glomus Tumor↗
PubMed2002

[Multivariate analysis of factors influencing the effect of radiosynovectomy].

OBJECTIVE: In this prospective study, the time to remission after Radiosynovectomy (RSV) was analyzed and the influence of age, sex, underlying disease, type of joint, and duration of illness on the success rate of RSV was determined. METHODS: A total number of 57 patients with rheumatoid arthritis (n = 33) and arthrosis (n = 21) with a total number of 130 treated joints (36 knee, 66 small and 28 medium-size joints) were monitored using visual analogue scales (VAS) from one week before RSV up to four to six months after RSV. The patients had to answer 3 times daily for pain intensity of the treated joint. The time until remission was determined according to the Kaplan-Meier survivorship function. The influence of the prognosis parameters on outcome of RSV was determined by multivariate discriminant analysis. RESULTS: After six months, the probability of pain relief of more than 20% amounted to 78% and was significantly dependent on the age of the patient (p = 0.02) and the duration of illness (p = 0.05), however not on sex (p = 0.17), underlying disease (p = 0.23), and type of joint (p = 0.69). CONCLUSION: Irrespective of sex, type of joint and underlying disease, a measurable pain relief can be achieved with RSV in 78% of the patients with synovitis, whereby effectiveness is decreasing with increasing age and progress of illness.

Arthritis, Rheumatoid↗